Emergency relay valve



Sept- 28, 1954 c. B. FITES ETA. 2,690,359

EMERGENCY RELAY VALVE Filed March 17, 1950 4 Sheets-Shes?I 1 )7 THEIRATTO NEYS- Sept. 28, 1954 c; a. FlrEs ETAL EMERGENCY RELAY VALVE 4Sheets-Sheet 2 Filed March 17, 1950 FIG. 3.

INVENTORSZ 651'; f @w )l/d) THEIR ATTORNE s.

Sept. 28, 1954 c. B. Fm-:s ETAL 2,690,359

EMERGENCY RELAY VALVE Filed March 17, 1950 4 Sheets-Sheet 3 THEIR A 1ORNEYS.

Sept. 28, 1954 c. B. F11-Es ETAL EMERGENCY RELAY VALVE 4 Sheets-Sheet 4Filed March 1'7, 1950 FIG. 5.

EYS.

INVENTORS:

' l THEIR ATTOR Patented Sept. 28, 1954 UNITED STATES PATENT OFFICEEMERGENCY RELAY VALVE Cyril B. Fites, St. Johns, and Stanley Ryan,Ferguson, Mo., assgnors to Wagner Electric Corporation, St. Louis, Mo.,a corporation of Dela- Application March 17, 1950, Serial No. 150,176

1 Claim. 1

This invention relates to relay valves of the kind used in fluidpressure brake systems for automotive Vehicles for applying fluidpressure toa iiuid operated brake cylinder located at a distance from amain source of uid pressure, such as in the case of brakes on a trailerof a tractor-trailer combination or on theV rear brakes or a truck witha long wheel base, so as to cause the remotely located brakes to operatein response to an operators action as quickly as the front Wheel brakesof the vehicle, said relay valve having therein an emergency means forautomatically applying the remotely located` brakes when the pressure inthe main reservoir falls below a predetermined value for any reason.

This invention is used in combination with a fluid pressure brakingsystem having a main reservoir, and auxiliary reservoir, brake operatingcylinders, and a brake application valve.

The principal object of this invention is to provide in a fluid pressurebraking system, a relay valve with an emergency feature therein whichgives a rapid and positive braking action,

Another object of this invention is to provide a valve which metersl theamount of pressure fluid applied to the remotely located brakes so thatlan operator can feel the application of said remotely located brakes andcontrol said application in proportion to the appiifati'on of hismanuali control means.

Still another' object isI to provide in a relay valve, an emergencymeans which When actuated allows pressure fluid to flow directly fromthe auxiliary reservoir to the brake operating cylinders without movingany part in the relay valve body portion which operates under normalnon-emergency conditions..

The invention consists in an; emergency valve mechanism comprising ahousing having a resilient means therein, a normally open exhaust valveoperatively connected to said resilient means, an exhaust` valve headadapted for closing said exhaust valve, a 'calife stem secured to saidexhaust valve head., saidvalve stem having a normally closed actuatingvalve secured t ereto and adapted for opening after said exhaust valvehas closed, and an independent emergency means con'lprisng an emergencyresilient means operatively conn cted 'to' the brake operating cylindersfor' allowing press fluid to beV supplied thereto, said' emergency.reiient means being responsiveto pressure from the reservoir forrendering said emergency means opera'- tive or inoperative.

The invention also consists in the parts and arrangements and in thecombination of parte hereinafter described and claimed.

In the acccmpanyrf.r drawings, which form part of this specificationand' wherein like nu, mei-als to liker parts wherever they occ l alongitudinal. crossesectional vieu7 of our emergency relay Valve,

Fig. 2 is a side View or the valve looking at the right side of thevalve as shown in Fig. 1,

Fig. 3 is a bottom View of the valve shown in Fig. l,

Fig. 4 is a diagrammatic View of a iiuid pressure braking system showinga longitudinal crosssectional view of the emergency relay valve in aslightly modied' form to permit an easier understanding of thedescription and operation of said device, and

Fig. 5' is a fragmentary diagrammatic view of a slightly modified formof an emergency means for the emergency relay valve shown in Fig. 4.

In Fig. 4 of the accompanying drawing, this emergency relay valve I isshown embodied in a system having a main reservoir i.' supplied withfluid under pressure from a source not shown and connected with saidemergency relay valve I by means of a line 3 and a main reservoir line iand an emergency line 5, an auxiliary reservoir 6 adapted for receivingpressure fluid from saidv main reservoir 2 and connected with theemergency relay valve I by an auxiliary reservoir line T, said emergencyrelay valve I and the auxiliary reservoir 5 being located near rearbrake operating cylinders B which receive pressure fluid from saidauxiliary reservoir e through a portion of said emergency relay valve Iand rear brake operating cylinder line 9, and a brake application valveIl@ connected with said main reservoir 2` by the line 3. Front brakeoperating cylinders l I are connected to the brake application Valve Iby means of a front brake operating cylinder line I2; The rear brakeoperating cylinders 3 are remotely located and may be on the trailer ofa tractor-trailer or on the rear brakes of a truck having a long wheelbase. The front brake operating cylinders II may be located onthe frontand/or the rear brakes of a tractor in a tractor-trailer combination oron the front brakes of a truck having a long wheel base.

The emergency relay valve I comprises a main valve body portion t3having rigidly secured thereto by means of machine screws It Withlockwashers l5, a relay valve body portion i5 and an emergency valvebody portion I'I'. Secured between said. main valve body portion i3 andsaid relay valve body portion I6 by its outer edge is a diaphragm I3having a central opening therein for receiving an exhaust valve stem I9rigidly mounted thereon by means of a diaphragm nut iid and a diaphragmplate 2l cooperating with a stop plate 22 mounted on said exhaust valvestem I9 on the opposite side of said diaphragm I8; Fittingcircumferentially over the exhaust valve stem i9 and mounted in the mainvalve body portion I3 are packing cups 23 and packing cup retainers 2li.The exhaust valve stem I9 is provided with an exhaust valve stem passage25 which connects a valve chamber 26 with an intermediate chamber 2l.

A cavity is provided in the main valve body portion I3 which inconjunction with the diaphragm I8 forms an application chamber 28. Acavity is also provided in the relay valve body portion I3 which inconjunction with the diaphragm I3 forms an equalizing chamber 29.

The equalzing chamber 29 is connected with the valve chamber 25 by meansof an annular passageway 35 formed between a cylindrical portion 3| inthe relay valve body portion IE5A and said exhaust valve stem I9 whichis in axial relation therewith. A diaphragm return spring 32 ispositioned over said cylindrical portion 3l so as to rest between therelay valve body portion I3 and the stop plate 22. The Valve chamber 23has an outlet port 33 therein for connection with the rear brakeoperating cylinder line 9 and the rear brake operating cylinders 8. Anexhaust-actuating Valve 34 is located within said valve chamber 2S. Theexhaust-actuating valve 3ft comprises an exhaust-actuating valve stem 35having an exhaust valve head 36 thereon with an exhaust Valve headinsert 31 therein, said exhaust valve head insert 3l being in axialalignment with the exhaust valve stem I9 to control the opening of theexhaust Valve stem passage 25 therein, and an actuating valve spring 38positioned over said exhaust-actuating valve stem 35 between the exhaustvalve head 35 and a rib section 39 which is a part of the relay valvebody portion I5. The exhaust-actuating valve stem 35 is extended abovesaid rib section 35 into an actuating chamber formed by an actuatingchamber cap II and the relay valve body portion I5. Secured to the upperend of the said exhaust-actuating valve stem 35 is an actuating valvehead 42 with an actuating valve head insert 43 therein in abuttingrelation to an actuating valve seat 44 located on said rib section 39for controlling the opening formed adjacent to said rib section 39between the valve chamber 26 and the actuating chamber 45. An auxiliaryreservoir port 135 is provided in the actuating chamber il@ as a meansfor connecting said actuating chamber M) with the auxiliary reservoirline l.

Secured between the main valve body portion I3 and the emergency valvebody portion I'I by its outer edge portion is an emergency diaphragm 45which together with the upper portion of said emergency valve bodyportion I'I forms an inlet chamber II'I, A primary emergency spring i8having therecn a primary emergency spring follower 29 with followerorices 55 therein is positioned in said inlet chamber Il and betweensaid emergency diaphragm 45 and a ange 52 in said emergency valve bodyportion I'I. The inlet chamber Ii'I has an opening 53 therein and aninlet port 54.

In the lower portion of the emergency valve body portion II is a checkvalve 55 for allowing the i'low of pressure fluid in only one direction,said check valve 55 comprising a slidable check valve head 55 with acheck valve head insertV cap 53 which forms a closure means for theemergency valve body portion Il. The lower portion of said emergencyvalve body portion II and the check valve spring cap 52 form a checkvalve chamber 6I.

A duct 62 connects the check valve chamber zontal passage 56, verticalpassage 5l, and passages 58 and B9 which lead into a relay valve bodyport 15 in the actuating chamber il@ in the relay valve body portion I5.

Slidably mounted on the opposite side of the emergency diaphragm :i6from the primary emergency spring i8 and in axial alignment therewith isan emergency valve 'H comprising an emergency valve stem l2 having anemergency valve stem passage I3 therethrough, an emergency valve head'ill with an emergency valve head insert 'E5 therein. A shoulder 'I5 inthe main Valve body portion I3 forms an emergency valve seat Il for saidemergency valve 1I.

A secondary emergency spring 'I8 is positioned between said emergencyvalve head 'III and a secondary emergency spring cap 79 which forms aclosure means for the main valve body portion I3. The secondaryemergency spring i8 will move the emergency valve step 'i2 rightwardlyto seat the emergency valve head insert 'I5 on the emergency valve seatIl if not prevented from doing so by action of the emergency diaphragmon the emergency valve stem 'I2 rightwardly to seat emergency spring cap'I9 and the emergency valve head I form a secondary emergency chamberEil which leads into the intermediate chamber 2l when the emergencyvalve head 'Ill moves away from the secondary emergency spring cap '19.

An annular exhaust chamber 8i which surrounds the emergency valve stem'l2 connects the intermediate chamber 2l with an exhaust port 82 whenthe emergency valve head insert I5 is not biased against the emergencyvalve seat ll.

Under normal inoperative conditions, the parts and combinations of partsare in positions as shown in Fig. 4 of the accompanying drawings. Themain reservoir 2 is under iluid pressure from any suitable source (notshown) When the pressure in said main reservoir 2 is suicient toovercome the check valve spring 59, pressure uid iiows from said mainreservoir 2 into the emergency line 5, the inlet port 54, into the inletchamber Il and through the opening 53 forcing the check valve to openthereby allowing pressure fluid to iiow into the check valve chamber 6I,the duct 52, the emergency application chamber r63, the main valve bodyport 613, into the passage 35, horizontal passage S6, vertical passage51, and passages 68 and 59 which lead into the relay Valve body port 1Q,the actuating chamber di), and through the auxiliary reservoir port 45,into the auxiliary reservoir line I and then into the auxiliaryreservoir 6. The only pressure difference existing between the inletchamber l? and the emergency application chamber 53 is that differencedue to the effects of the check valve spring 59. When the brakeapplication valve Ii! is actuated pressure iiuid passes from the mainreservoir 2, through the line 3 into said brake application valve I 5,the main reservoir line ll into the application chamber 28 to force thediaphragm I8 upwardly. Since the Volume of the application chamber issmall, pressure can be built up on the under side of the diaphragm i8very quickly. This pressure forces the diaphragm I8 upwardly compressingthe diaphragm return spring 32 and causing the exhaust valve stem IS tomove upwardly until it engages the exhaust valve head insert 31 creatingan air sea1 therebetween thus closing the exhaust valve stem passage 25in said exhaust valve stem I9. Continued upward movement of saiddiaphragm I8 and said exhaust valve stem I9 forces the exhaust-actuatingvalve 34 upwardly compressing the actuating valve sprintr 38 andcausingthe actuating valve head insert 43 to unseat from the actuating. valveseat M, thereby allowing pressurev fluidfrom the auxiliary reservoir 6to. come therefrom. through the aux.- iliary reservoir line ll, theauxiliary reservoir port 45; the actuating. chamber 40, the valvechamber 26, the outlet port 33. and. out through the rear brake.-operating cylinder line Sinto the rear brake operating cylinders 8.

While pressure fluidi is flowing through the valve chamber 2li4 to therear brake operating cylinders. 8 a portion of said pressure fluid alsoflows through the clearance or passageway 3l) between the exhaust valvestem l9- and the cylindrical portion 3l of. the relay valve body portionlli into the equaliz-ing chamber 29. The passageway 3i! is slightlyrestricted sol as to prevent a pressure build up in the equali-Zingchamber 29 ahead of that. pressure which results. from, the flow ofpressure iiuid to the rear brake operating cylinders 8 whereby such a.condition if not prevented would cause a fluttering. action of themovable parts in the relay valve body portion I6. As the pressure fluidenters. the. equalizing chamber 2Q a pressure is. created therein which.in turn creates a force on the diaphragm I8.. The pressure in theequalizing chamber 29 will therefore increase until the. resultantforce. on. thev upper side of the diaphragm. i8', due to. the presencevof the pressure fluid and the forcesv ofthe diaphragm return spring.3.2- and they actuating valveI spring 38;, overcomes the force acting onthe underside of the diaphragm i8. in the.- application. chamber 2.8. Asthis condition occurs. the diaphragm. |.8 andthe attached exhaust valvestem l 9 are. moved downwardly to allow the exhaust-actuating valve Stito assume a lapped position; that is,. a. position where the actuating,valve head' insert 43 is resting. upon the actuating. Valve seat 4.4.and. the exhaust valve head insert 3.1. isstill held against the end orthe exhaust, valve stem ligt.. Thus.l the pressure. in. the equalizingchamber 2.9,. which is equal to the pressure in the rear brake operatingcylinders 8 and in the valve. chamber 25 remains constant until'. afurther braking. application is made by the operator by increasing. theiiu-i'dpres.- sure in the application chamber 28 whereupon the diaphragmIS' is again moved upwardly.` The exhaust valve stem i9 carried by saiddiaphragm i8, by virtue of its contact with they exhaust valve headvinsert 31, will. again unseat the actuating Valve head insert 'i3 fromthe actuating valveseat 4'4 permitting a. ow of pressure fluid from. theauxiliary reservoir 6 as previously described. Consequently, it becomesevident that a given pressure in the application chamber 223 willproduce a proportional pressure in the equalizing chamber 2a and therear brake operating cylinders' 8; The operator feel is produced by the`forces. acting on the upper' side ofthe diaphragm I/S created primarilyby the iiuid' pressure acting on said diaphragm I8' in the equalizingchamber 29.

When the operator reduces the pressure in the application chamber 23 byexhausting the pressure huid at the brake application valve l'll, thediaphragm l is moved downwardly under the inuence of the greaterpressure acting. within the equalizing chamber 29 and the diaphragmreturn spring 32. The actuating valve head insert i3 having seated priortov the pressure reduction now being. describediurther movementoitheexhaust-actuatingvalve 34 downwardly is prohibited. When there is. acomplete. reduction of the'. pres- Sure formerly developed in thelapplication. chamber 23 the. diaphragm. la andY the exhaustvalve stem-I8 move sufiicientlydownward to break the contact between the end ofsaid exhaust valve stem t9 and the exhaust valve head insert 31 therebyopening the exhaust valve stem passage 25 in said exhaust valve stem i9.rI'he pressure fluid in the equalizing chamber 29, the valve chamber26', the rear brake operating cylinder line 9 and therear brakeoperating cylinders 8 is then exhaustedthrough the exhaust valve stempassageI 25 the intermediate chamber 21, the annular exhaust chamber 8|,andthe exhaustfport 82 into the atmosphere;

When there is suiii'cient fluid pressure within the main reservoir 2 theparts and combinations of. parts are in the position as shown in Fig. 4,that is, the primary emergency spring 48 forces the emergency diaphragm46 leftwardly until said emergency diaphragm 46 engages the end of theemergency valve stem 72 thereby closing the emergency valve' stempassage 13 and forcing the emergency valve head 'M against the secondaryemergency spring cap T9 andcom-pressing the secondary emergency springiii..

Therefore, so: long as; the pressure inthe main reservoir 2 and. itsassociated pipe system remain above a predetermined Value, the parts inthe relay valve' body portion IB operate exactly as herein-beforedescribed.. But should there be, for any` reason such. as a break in.the emergency line 5, a. suflicient lowering of fluid pressure inthezmainvreservoir 2, the emergency line 5 and the inlet chamber ll'.,the greater: liu-id pressure. in the emergency application chamber 63,which is the same as the fluid pressure the auxiliary reservoir b, willforce the emergency diaphragm 4b rig-htwardly against the resistance otthe primary emergency spring i. The rightwa1fd-movemen-t. of theemergency diaphragm 45. allows the secondary emergency spring. 'i toforce the emergencyv valve. 'F.l to4 move rightwardl-y therebyuriseating the emergency valve head. "itv from the secondary emergencyspring cap 19, seating the emergency valve head insert. 75 against. theemergency valve seat Tl.. Further rightward movement. of said emergencydiaphragm 46 will cause said emergency diaphragm. 45. to unseat.- fromthe endet the emergency` valvestem 'l2 thereby open'- the emergencyvalve stem passage i3 thus allowing pressure fluid toilow from theauxiliary reservoir S, into. the auxiliary reservoir line 'l through theauxiliary reservoir port d intoA the actuating chamber about. throughthe relay valve body port lg, the passages 39 and. 58, theverticalpassage. 5L the horizontal passa-ge, the passage 55,. through tbe main.valve. body port into the emergency application chamber throughemergency valve stem. passage, is in the emergency valve stem 72,. thesecondary emergency chamber 811,. the. intermediate chamber 2l'A upthrough the exhaust valve stem passage. 25 into` the. valve chamber 2E;through the. outlet port 33 into. the rear brake operating cylinder line9. and rear brake operating. cylinders. ii. Thus, the emergency fea.-ture of this device does not. operate any of. the internal parts. of.said device which are operated under normal conditions.

The brakes will remain in the applied position until the brake inemerger y line 5 or any other defect causingA an insufficient pressureto be exerted against the emergency diaphragm ab has been repaired so asto. build up a pressure in the inlet chamber All' sufciently toneutralize the pressure acting on: the' opposite side of the emergencydiaphragm 26 so that the primary' emergencyf spring @Si can force theemergency diaphragm e6 to the left against the end ofthe emergency valvestem 'l2 thereby closing the emergency valve stem passage 'i3 andlifting the emergency valve head insert l from the emergency valve seatl? thereby exhausting the pressure Iiuid from the rear brake operatingcylinders 8 through the previously described passages, ports andchambers out through the exhaust port 82. v

A modied form of this device is shown in Fig. 5. In this modificationall parts are the same as in the principal form of the invention but forthe addition of a diaphragm separator body portion 83 and some partslocated within the emergency valve body portion Il. The outer edgeportion of the emergency diaphragm 48 is secured between the main valvebody portion i3 and the diaphragm separator body portion 83. Theemergency diaphragm d8 together with the right end of the main valvebody portion i3 form the emergency application chamber 63 which containsa ring 88 which decreases the effective area of said emergency diaphragm46.

Secured between the diaphragm separator body portion 83 and theemergency valve body portion l1 by its outer edge portion is a thirddiaphragm 85 which together With the diaphragm separator body portion 83forms a vented chamber 88 in which is slidably mounted a piston 8'!having an aperture 88 therein, said piston 8'! being in abuttingrelationship with the emergency diaphragm 46 and the third diaphragm 85.The vented chamber 86 contains a vent (not shown) so that said ventedchamber 86 is maintained at atmospheric pressure at all times. The thirddiaphragm 85 has a greater eiective area than the emergency diaphragm 46because of the ring 84:

A follower member 48a having follower orifices 58 is positioned in theinlet chamber 41. The inlet chamber 41 is separated by the check valve55 from the check valve chamber 6I having the duct 62 leading therefrom,which duct passes through the diaphragm separator body portion 83 intothe emergency application chamber 63.

The operation of the relay portion of the modified form of thisemergency relay valve is the same as that of the principal form. Theoperation of the emergency means of the modied form is as follows. Undernormal conditions the force acting on the third diaphragm i85 is greaterthan the force acting on the emergency diaphragm 46 even thoughsubstantially the same fluid pressure is acting thereon. Because of thegreater effective area of the third diaphragm 85 a greater force acts onsaid third diaphragm 85 which, through the piston 81, forces theemergency diaphragm 46 against the emergency valve stem l2 closing theemergency valve stem passage 13 therein. During an emergency condition,assuming that the pressure fluid in the inlet chamber 41 has been lostto the atmosphere due to a rupture in the connecting line or for anyother reason, the fluid pressure in the emergency application chamber 63forces the emergency diaphragm 46 away from the end of the emergencyvalve stem 12 allowing the passage of pressure uid from the auxiliaryreservoir 6 to the rear brake operating cylinders 8. The only resistanceto the movement of the emergency diaphragm 46 is the force exerted onsaid emergency diaphragm 46 in said vented chamber 86 due to theatmospheric pressure existing therein. The forces on the third diaphragm85 are neutralized since atmospheric pressure prevails on vboth sides ofthe third diaphragm 85 when there is a complete rupture of the emergencyline 5 leading into the inlet port 54.

The elimination of the primary emergency spring 48 of the principal formresults in an improvement in the operation of the emergency means of theemergency relay valve. This modification allows the setting of thetrailer or rear brakes during an emergency condition when the pressurein the auxiliary reservoir 6 is too low to overcome the force of theprimary emergency spring 48 in the principal embodiment to break thecontact between the end of the emergency valve stem 'l2 and theemergency diaphragm 46.

The elimination of the primary emergency spring 48 in the principal formalso eliminates the possibility that a leak in the system would allowthe force of primary emergency spring 48 to overcome the force exertedon the emergency diaphragm i6 by the pressure uid in the emergencyapplication chamber 63 to again close the emergency valve stem passage'I3 and move the yemergency valve stem 'l2 sufiiciently leftwardly toexhaust the pressure fluid from the rear brake operating cylinders 8.

What I claim is:

In a fluid pressure braking system having brake operating cylinders, amain reservoir and an auxiliary reservoir, lines connecting said mainreservoir with said auxiliary reservoir and said auxiliary reservoirwith said brake operating cylinders, a uid pressure operated valvemechanism interposed in said lines for controlling the flow of pressurefluid from said auxiliary reservoir to said brake operating cylinders, aseparate line for connecting said main reservoir with said fluidpressure operated valve mechanism, an application valve interposed insaid separate line for controlling the flow of pressure fluid to saiduid pressure operated valve mechanism, and a check valve in one of saidrst mentioned lines for preventing return flow of pressure fluid to saidmain reservoir; an independently operable means associated with saidfluid pressure operated valve mechanism responsive to the actuation ofsaid application valve for permitting flow of pressure fluid from saidauxiliary reservoir to said brake operating cylinders, and a secondindependently operable means associated with said fluid pressureoperated valve mechanism operable below a predetermined main reservoirpressure for automatically supplying pressure fluid to said brakecylinders from said auxiliary reservoir; said second independentlyoperable means comprising a pressure responsive emergency means subjectto the pressure in said main reservoir on one side and to the pressureof the auxiliary reservoir on the other side, an emergency valve stemhaving a passageway therein, a resilient means for normally biasingysaid pressure responsive emergency means against said valve stem forcontrolling said passageway, a normally open exhaust passage about saidvalve stem for venting fluid from said brake cylinders by operation ofsaid rst mentioned independently operable means, a valvular means onsaid valve stem for controlling said exhaust passage, and a secondresilient means for biasing said valvular means to a passage closingposition.

References Cited in the le of this patent UNITED STATES PATENTS NumberName Date 1,438,317 Lewis Dec. 12, 1922 2,018,212 Johnson 1 Oct. 22,1935 2,203,042 Boldt June 4, 1940 2,289,559 Turek July 14, 19422,441,050 Wiegers May 4, 1948

